[Pc_Support] Case airflow dynamics?

[Justin M. Keyes]

On 4/2/06, Jason Boxman <jasonb at edseek.com> wrote:
> Anyone know of any good resources on case airflow dynamics?  I've been trying
> to reduce the noise signature of my systems without overly compromising
> airflow and with it drive and CPU temperature, but have found amusing
> results.
>
> Perhaps obvious, but on one system with 3 x 300GB ATA disk in 5.25" bays one
> bay down from the top of a large tower case (the top bay has, by general
> convention, the DVD-ROM drive) I found that simply removing the lowest front
> face plate resulted in a 3-5C drop in drive temperature.  Effective, but
> somewhat ugly looking.
>
> Another more amusing example, I added a 12cm fan bay cooler that occupies 3 of
> 6 5.25" bays in another tower case.  The four disk drive cage in the back
> above the PSU with four ATA disk and two 8cm fans side by side aren't any
> cooler with the 12cm bay cooler than without.  I almost find that comical as
> I blew $23 shipped on the cooler.  It looks neat, though.
>
> Perhaps in the future I need to buy those expensive airflow friendly cases
> instead of a less expensive, random case.  (Although my AOpen AH700A tower
> case wasn't exactly cheap and is quite roomy.)

Probably you know this already, but, Bryan's advice over the years has been:
(1) airflow coming in (from the front) is more important than
airflow/fans in the back, i.e., getting cool air IN is more important
than getting hot air OUT...
(2) the fans should generally be blowing in the same direction--having
a fan blowing out of the back, and another blowing out of the top, and
another on the side, is counter-productive;
(3) contrary to common sense, a closed case (with proper airflow) is
cooled better than an open case. Not sure how that relates to your
experiences with the front slot.

--
Justin M. Keyes